\(C=\frac{\left(-3\right)^{10}.15^5}{25^3.\left(-9\right)^7}\)
\(=\frac{\left(-3\right)^{10}.\left(3.5\right)^5}{\left(5.5\right)^3.\left(-3.3\right)^7}\)
\(=\frac{\left(-3\right)^{10}.3^5.5^5}{5^3.5^3.\left(-3\right)^7.3^7}\)
\(=\frac{\left(-3\right)^3.1.5^2}{5^3.1.1.3^2}\)
\(=\frac{\left(-3\right).1.1}{5.1.1.1}\)
\(=-\frac{3}{5}\)
1.c,
\(\frac{\left(-3\right)^{10}.15^5}{25^3.\left(-9\right)^7}=\frac{3^{10}.\left(3.5\right)^5}{\left(5^2\right)^3.-\left(3^2\right)^7}\)\(=\frac{3^{10}.3^5.5^5}{5^6.-3^{14}}=\frac{3^{15}.5^5}{5^6.-3^{14}}\)\(=\frac{3.1}{5.-1}\)\(=\frac{3}{-5}=\frac{-3}{5}\)
chúc bn học tốt!